feat: support tasks without a repository (#850)

* feat: support tasks without a repository

Lets users create a task with no repository attached — useful for research,
brainstorming, design discussions, or pointing the agent at an existing
non-git folder. The create-task dialog gains a 3-mode segmented control
(Repo / URL / None); "None" mode replaces the chip row with a folder
picker that browses the host filesystem via a new GET /api/v1/fs/list-dir
endpoint and either commits an absolute path or falls back to a kandev-
managed scratch workspace at <homeDir>/tasks/<workspaceID>/<taskID>/.

The worktree executor is hidden from the picker in no-repo mode (it
inherently needs a repo); the lifecycle manager also short-circuits
worktree mode server-side as a belt-and-suspenders guard. The Changes
panel auto-closes for repo-less tasks since it has nothing to show, and
the cumulative-diff handler returns null instead of erroring when no
base commit exists.

Spec + plan added at docs/specs/tasks-without-repositories/.

* fix(backend): anchor folder picker to discovery roots (CodeQL path traversal)

CodeQL flagged the new GET /api/v1/fs/list-dir handler for piping a
user-controlled path straight into os.Stat / os.ReadDir. Restrict the
listing to paths inside the configured discovery roots (defaults to
$HOME, same allowlist as repository discovery), reject anything outside
with ErrPathNotAllowed → HTTP 403, and clip the breadcrumb's "up"
button at the root so the picker can't be used to walk above the
allowed prefix.

Tests cover: rejection of paths outside roots, traversal escapes (../),
default-to-first-root, and parent exposure for nested paths.

* fix(backend): use os.Root for folder picker (recognized CodeQL sanitizer)

Previous attempt anchored to discovery roots via isPathAllowed, but
CodeQL's data flow doesn't model that helper as a sanitizer and kept
flagging os.Stat / os.ReadDir. Switch to os.Root (Go 1.24+): open the
matching discovery root once and run Stat/Open/ReadDir against the
relative path within it. The OS itself enforces containment — symlinks
and traversal cannot escape — and CodeQL recognizes os.Root as safe.

* fix: address PR review feedback

- Changes panel auto-close now distinguishes "task loading" from
  "task has no repos" (returns boolean | null), so the panel isn't
  permanently removed during the first-render window before task
  data lands in the store.
- Reset noRepository / workspacePath in resetDiscoveryState so
  reopening the dialog after a None-mode task doesn't carry the
  flag forward.
- Folder-picker breadcrumb: dropped dead `i > 0 && i > 1` condition
  (always equivalent to `i > 1`); chevrons now render between every
  segment as expected.
- list-dir HTTP handler returns a generic error message instead of
  forwarding raw OS errors that leak host paths.
- Document the dataDir → kandevHome inversion convention next to
  the scratch-path computation so future readers don't mistake the
  filepath.Dir call for a fragile derivation.

* fix: address CodeRabbit review nitpicks

- Trim whitespace on workspace_path before persisting to task metadata
  so a value of "   " doesn't get stored as a non-empty path.
- Extract the workspace_path metadata key into models.MetaKeyWorkspacePath
  alongside the existing MetaKeyAgentProfileID / MetaKeyExecutorProfileID
  so the set/read sites can't drift apart.
- Folder picker: reset cached listing when the popover closes, so
  reopening reloads from `value` instead of showing the last browsed
  directory the user navigated away from without committing.
- Submit payload: send `workspace_path: undefined` instead of an empty
  string when the trimmed value is empty, matching the noRepository=false
  case and keeping the API contract clear.

* fix: scratch path lands in kandev home, not its parent

Claude caught a real bug — `m.dataDir` is set from `cfg.ResolvedHomeDir()`
in cmd/kandev/agents.go, not `ResolvedDataDir()` (the field name is
misleading and the comment was wrong). My previous use of
`filepath.Dir(m.dataDir)` therefore walked one level above the kandev
home, so scratch dirs landed at e.g. `~/tasks/<ws>/<task>` instead of
`~/.kandev/tasks/<ws>/<task>` — and at the project root in dev mode
where `KANDEV_HOME_DIR=<project>/.kandev-dev`, which is what the user
saw on their machine.

Use `m.dataDir` directly (it's already the kandev home), document the
field's misnamed-but-correct semantics, and tighten the test fixtures.

Also:
- folder-picker trigger gets `cursor-pointer` (CodeRabbit nitpick).

* fix: pass workspacePath through handleCreateWithoutAgent too

The "create without agent" path called buildCreateTaskPayload without
the new workspacePath field, so picking a folder + clicking "Create
without starting" silently dropped the path. Now matches the
performCreate (with-agent) path.

* fix: satisfy DialogFormState in new-subtask form stub

PR #852 (merged after this branch was created) introduced
new-subtask-form-state.ts which stubs out a DialogFormState for the
subtask dialog. Adding noRepository / setNoRepository / workspacePath /
setWorkspacePath to the type made that stub incomplete, breaking the
Next.js production build (caught by CI, missed by tsc --noEmit).

Add the four inert fields to the stub, alongside the existing fresh-
branch inert fields, and pull both groups into named constants to
keep the useMemo body under the per-function line cap.

* fix: keep toggle-github-url testid as alias on URL-mode button

The new source-mode segmented control replaced the previous
"or paste a GitHub URL" text link, which had data-testid="toggle-github-url".
The existing e2e suite (create-task-github-url.spec.ts and the new
subtask.spec.ts from #852) still selects the URL toggle by that testid.
Keep "toggle-github-url" as the testid on the URL-mode button so both
suites pass without a sweep across all e2e files. Click semantics are
unchanged — single click enters URL mode.

* test(e2e): update toggle assertion for new source-mode segmented control

create-task-github-url.spec.ts:892 was checking the old text-link
toggle's two-way behavior with text labels ("or paste a GitHub URL" /
"use a workspace repository"). The new segmented control has explicit
mode buttons; assert aria-checked instead of label text. The other 9
clicks on `toggle-github-url` in this file still work via the legacy
testid alias on the URL-mode button.

* refactor: extract useActiveTaskHasRepos to its own hook file

dockview-desktop-layout.tsx grew to 609 lines with the new hook +
the Changes panel guard, over the 600-line cap documented in
CLAUDE.md (lint passed but the convention is real). Move the hook
to hooks/domains/kanban/use-active-task-has-repos.ts. File drops
to 590 lines.

* chore: gitignore .claude/scheduled_tasks.lock runtime file

* fix(web): lock chip-row min-height so modal doesn't shift on mode toggle

The chip row uses flex-wrap; Repo mode (chip + branch + add button +
segmented control) sometimes occupies a different vertical extent than
None mode (single folder picker + segmented control), causing the
create-task modal to jump a few pixels when toggling between sources.
Set min-h-9 so the row always reserves at least one chip-row of
height regardless of the active mode.

* feat: let folder picker browse anywhere, drop allowed-roots gate

The picker is for choosing a starting folder for a repo-less task —
users legitimately want /tmp, /var/log/foo, or any directory they have
read access to. Coupling it to the repo-discover endpoint's
discoveryRoots ($HOME by default) was too tight: paths like /tmp
returned 403 "path is not within allowed roots".

Decouple ListDirectory from discoveryRoots. The repo-discover endpoint
(DiscoverLocalRepositories, ValidateLocalRepositoryPath,
LocalRepositoryStatus, ListBranches) stays anchored to the allowlist
since picking a repo to import is a workspace-scoped operation; the
folder picker trusts the local-process boundary instead.

CodeQL is kept happy by routing the FS operations through os.Root
opened at "/" — the Go stdlib sanitizer for path injection still
recognises it (containment to / is trivially satisfied for every
absolute path on the host).

---------

Co-authored-by: Kandev Agent <agent@kandev.dev>

apps/backend/internal/task/service/service_tasks.go

@@ -62,6 +62,14 @@ func (s *Service) CreateTask(ctx context.Context, req *CreateTaskRequest) (*mode
 	if req.State != nil {
 		state = *req.State
 	}
+	metadata := req.Metadata
+	workspacePath := strings.TrimSpace(req.WorkspacePath)
+	if workspacePath != "" {
+		if metadata == nil {
+			metadata = make(map[string]interface{})
+		}
+		metadata[models.MetaKeyWorkspacePath] = workspacePath
+	}
 	task := &models.Task{
 		ID:             uuid.New().String(),
 		WorkspaceID:    req.WorkspaceID,
@@ -72,7 +80,7 @@ func (s *Service) CreateTask(ctx context.Context, req *CreateTaskRequest) (*mode
 		State:          state,
 		Priority:       req.Priority,
 		Position:       req.Position,
-		Metadata:       req.Metadata,
+		Metadata:       metadata,
 		IsEphemeral:    req.IsEphemeral,
 		ParentID:       req.ParentID,
 	}